4: Determining caffeine in beverages using HPLC (and UV-vis)
- Page ID
- 401292
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After completing this module, students will be able to:
- Explain the principles of liquid-liquid partitioning.
- Explain the effect of solvent polarity on retention times.
- Explain the effects of isocratic and gradient methods on retention times and peak shape.
- Interpret chromatographic data to identify components of a mixture and determine their concentration.
This lab manual includes a brief overview of HPLC. For fuller coverage of the topic, refer to the textbook for CHEM 401. Libretexts also has a similar text (see Ch 12 of Analytical Chemistry 2.1 (Harvey)).
- 4.2: High performance liquid chromatography
- High performance liquid chromatography (HPLC) makes use of a high pressure pump to deliver a mobile phase solvent at a uniform rates at pressures. The most obvious advantage of HPLC over gravity liquid chromatography is that samples can be separated much more quickly and with reproducible elution times.